Beverage preparation machine

ABSTRACT

The present invention provides a beverage preparation machine comprising a housing; a reservoir for containing a liquid, wherein the reservoir is situated within the housing; a dispensing outlet for dispensing the liquid; a pump situated between the reservoir and the dispensing outlet; a user input means situated on an outer surface of the housing; and a pump controller configured to operate the pump for conveying liquid from the reservoir to the dispensing outlet for dispensing the liquid, wherein the input means is capable of communicating with the pump controller in order to initiate an operation of the pump; and the pump controller is configured to operate the pump based on a characteristic of the previous operation of the pump.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Patent Application No.16/471,955, filed on Jun. 20, 2019, which was the § 371 National StageEntry of Patent Cooperation Treaty (PCT) Application No.PCT/GB2017/053882, filed on Dec. 22, 2017, the entire contents of bothof which are hereby incorporated by reference herein, for all purposes.

DETAILED DESCRIPTION

The present invention relates to a beverage preparation machine and amethod for operating the beverage preparation machine.

Beverage preparation machines are required to dispense definedquantities of liquid either directly into a vessel (such as a cup), orinto a beverage preparation package in order to prepare a beverage (suchas coffee or tea). In the latter case, the prepared beverage can then besubsequently dispensed into a vessel. The ability to dispense consistentvolumes of liquid (referred to herein as a vend) is important so thatthe user can be confident of the volume of liquid that is going to bedispensed into the vessel. This avoids potential mess associated with agreater than expected volume or the disappointment associated with aless than expected volume.

The consistency of the dispensed volume is particularly important inrelation to beverage preparation machines that provide the liquid to abeverage preparation package. The beverage preparation package isdesigned for use with a defined volume of liquid in order to produce theoptimum final beverage. Variability in the dispensed volume can lead tovariability in the quality of the final beverage and consumerdissatisfaction.

In the prior art, the beverage preparation machines use a flowmeter thatmonitors the fluid being dispensed from the beverage preparationmachine. This flowmeter can feedback the volume of liquid that has beendispensed and thus ensure that the dispensing of the liquid occurs untilthe correct volume has been dispensed. The presence of a flowmetercontributes to a consistent vend but adds to the cost of the beveragepreparation machine.

The present inventors have found that the volume of liquid dispensedfrom a beverage preparation machine that utilises a pump can vary basedon the operational history of the pump. This is demonstrated by FIG. 1.FIG. 1 depicts the volume of liquid that is dispensed from a beveragepreparation machine that was vended 21 times in a row, each venddirectly after the last. It can be seen that the volume of the dispensedliquid steadily decreases with each vend even though the operationalparameters of the pump are kept constant.

It is therefore an aim of the present invention to provide a beveragepreparation machine with a consistent vend volume but with a reducedcost and/or complexity of construction.

Accordingly, the present invention provides a beverage preparationmachine comprising: a housing; a reservoir for containing a liquid,wherein the reservoir is situated within the housing; a dispensingoutlet for dispensing the liquid; a pump situated between the reservoirand the dispensing outlet; a user input means situated on an outersurface of the housing; and a pump controller configured to operate thepump for conveying liquid from the reservoir to the dispensing outletfor dispensing a liquid, wherein the input means is capable ofcommunicating with the pump controller in order to initiate an operationof the pump; and the pump controller is configured to operate the pumpbased on a characteristic of the previous operation of the pump.

In this way, the pump controller is able to adjust the operation of thepump based on the previous operation of the pump. This enables anincrease in the consistency of the dispensed volume from the beveragepreparation machine without the need for a flowmeter.

In particular, the beverage preparation machine may not comprise aflowmeter for measuring the volume of liquid conveyed from the reservoirto the dispensing outlet. Preferably, the beverage preparation machinedoes not comprise a flowmeter at all.

The beverage preparation machine is capable of providing discretevolumes of liquid, either for preparing a beverage within the beveragepreparation machine or for preparing a beverage externally to thebeverage preparation machine.

The beverage preparation machine has a housing. The form of the housingis not particularly limited so long as it performs the basic function ofhousing beverage preparation machine components. The housing can beformed of plastic and/or metal material.

The beverage preparation machine has a reservoir for containing aliquid. For example, the reservoir may have an internal volume of 1 L ormore, 2 L or more, or 5 L or more. The beverage preparation machine canthen be filled with sufficient liquid for multiple discrete vends. Inthis way, the beverage preparation machine does not need to be connectedto a water supply. Where the beverage preparation machine is connectedto a water supply, the reservoir may be relatively smaller and simply bea region where the liquid is held prior to being pumped fordispensation.

The dispensing outlet of the beverage preparation machine is connectedto the reservoir such that liquid can be conveyed from the reservoir tothe dispensing outlet. The beverage preparation machine may comprisepipes or tubing suitable for conveying liquid connecting the reservoirto the outlet. The dispensing outlet may be in the form of a liquidinjection needle. This form allows the outlet to pierce a beveragepreparation package when a beverage preparation package is utilised withthe beverage preparation machine. The dispensing outlet may be made frommetal.

As noted above, a pump is situated between the reservoir and thedispensing outlet. In this way, the pump can be operated in order toconvey liquid from the reservoir to the outlet when dispensing.

When dispensing is not required the pump does not operate and liquid isnot conveyed from the reservoir to the outlet. The beverage preparationmachine may have additional valves that ensure liquid is not conveyedwhen dispensing is not required.

The form of the pump is not particularly limited. However, the pump istypically one which exhibits a varying efficiency based on its operationhistory. Such a pump may be a reciprocating positive displacement pump.In particular, the reciprocating positive displacement pump may comprisea shuttle mechanism. It has been found that the present invention isparticularly useful for a reciprocating positive displacement pump witha shuttle mechanism and especially one that utilises a change inmagnetic field for causing the reciprocating action. Such a pump hasbeen shown to have an efficiency that decreases with multiple operationsin the beverage preparation machine.

The user input means situated on the outer surface of the housingprovides a way for the user to control the beverage preparation machine.The user input means may be in the form of at least one button. The atleast one button can be used to initiate the dispensation of the liquid.The user input means may comprise a plurality of buttons that arecapable of initiating different forms of dispensation of the beveragepreparation machine. For example one button may be used for a relativelysmall volume dispensation while another button may be used for arelatively large volume dispensation. Alternatively, the user inputmeans may be in the form of a touch pad which may contain multipleoptions for the user.

The operation of the pump in the beverage preparation machine iscontrolled by a pump controller. The pump controller is capable ofreceiving a signal from the input means and then operating the pumpaccordingly to provide the required volume of liquid. The pumpcontroller is configured to store aspects of the operational history ofthe pump and to adjust the control of the pump operation accordingly. Inthis way, the pump controller is able to adjust the operating parametersof the pump so as to compensate for expected variability in thedispensed volume of liquid. The pump controller is programmed with therequired operational changes for compensating volume variability. Thisavoids the need for feedback from the machine and negates the need forthe flowmeter that is utilised in the prior art.

Various characteristics of the operational history of the pump mayaffect the subsequent dispensed volume. One particular aspect of theprevious operation of the pump that may affect the vending volume is thetime that has elapsed since the previous operation of the pump. It isbeen found that the performance of pumps can exhibit a form ofhysteresis. In other words, the efficiency of the pump can decrease withuse and then only recover after a sufficient resting time. Therefore,the time that has elapsed since the previous operation of the pump is animportant parameter that will affect the volume that will be vended fora given operation time of the pump.

The pump controller can be configured to account for thischaracteristic. For example, if the time that has elapsed since theprevious operation of the pump is below a critical value then the pumpcontroller can be configured to adjust the next operation of the pump soas to compensate for the expected efficiency decrease of the pump.Alternately, if the time elapsed is greater than the critical value, thepump controller may be configured to operate the pump with the sameparameters as the previous pump operation. This accounts for thehysteresis of the pump and acknowledges that there may be a particulartime frame over which the pump will recover its efficiency. The criticaltime may be, for example, 30 seconds, may be one minute, may be twominutes, may be four minutes, or may be five minutes. Typically, thecritical time is a time within the range of from about 10 seconds toabout 5 minutes, typically no more than about 4 minutes, typically nomore than about 3 minutes. The particular critical time will depend onthe specific configuration of the beverage preparation machine.

The pump controller can also be configured to take into account the timethat has elapsed between each of a plurality of previous operations ofthe pump. For example, the pump controller may take into account thetime that has elapsed between the last two operations of the pump, oreach of the last three operations of the pump, or each of the last fouroperations of the pump, or each of the last five operations of the pump,alternatively each of the last six, seven, eight, or nine or moreoperations of the pump. In this manner, multiple recent operations, thatwouldn't have allowed the full recovery of the efficiency of the pumpand instead result in an accumulative decrease in the efficiency of thepump can be compensated for. For example, if the last four previousoperations of the pump had a time that has elapsed between each of themof less than the critical value then a different operation of the pumpmay be required compared to the scenario where only the previous twooperations of the pump had a time that has elapsed between each of themwhich was less than the critical value.

The operation of the pump may be adjusted based on the frequency of aplurality of previous operations of the pump. This again can takeaccount of the accumulative effect of multiple recent dispensations. Inthis way, the pump controller may be configured to account for the timeframe over which the previous operations of the pump (for example 5operations) have occurred and so create an average frequency for thoseprevious operations and adjust the next operation of the pumpaccordingly. Conversely, the pump controller may be configured toaccount for the number of operations that have occurred in a previousdefined time period. For example, if five vends have occurred in thelast four minutes then a different operation of the pump may be requiredcompared to the scenario where only two vends had occurred in the lastfour minutes. The previous defined time period can be a time period inthe range of from about 10 seconds to about 5 minutes, for instance oneminute, two minutes, three minutes, four minutes or five minutes, or adifferent time period depending on the configuration of the beveragepreparation apparatus. Again, this allows compensation for theaccumulative effect of multiple recent vends.

The pump controller can be configured to take account of variouscombinations of historical operational data. For example, the pumpcontroller can be configured to account for both the time that haselapsed since the previous operation and the frequency of a plurality ofprevious operations and so compensate accordingly for the relativeeffects of these two aspects.

The decrease in efficiency with each variable can be investigatedempirically and may be dependent on the particular beverage preparationmachine configuration that is utilised. The effect of these variablesmay be observed and the pump controller configured accordingly tocompensate for the efficiency effects of these variables. This can havea varying degree of complexity. For example, a simple adjustment that isonly based on a time that has elapsed since the previous operation ofthe pump will advantageously provide a degree of compensation and sowill be beneficial. However, if further increases in consistency arerequired then additional variables can be taken into account such as thetime that has elapsed between a plurality of previous operations of thepump.

As noted above, the pump controller is configured to operate the pumpaccording to a characteristic of the previous operation of the pump. Inthis way, the pump controller is able to vary an operational parameterof the pump based on the characteristic of the previous operation of thepump.

That operational parameter may be the time that the pump is operatedfor. For example, if it has been found that the pump efficiencydecreases with an increasing amount of recent dispensations (forinstance within a defined time period), then the pump controller can beconfigured to increase the time of operation of the pump based on therecent dispensations so as to ensure the same volume of liquid isconveyed from the reservoir to the outlet for each vend regardless ofthe operational history of the pump. As noted above, the amount of timecompensation that is required can be investigated empirically and thepump controller can then be programmed accordingly.

A further parameter of the operation of the pump that can be controlledby the pump controller is the speed of operation of the pump. Again, ifit is found that the flow rate of the liquid being conveyed from thereservoir to the outlet decreases with multiple recent dispensations,even though the speed of the pump remains the same, then the speed ofthe pump may be increased in order to compensate for this loss ofefficiency. Again, this can be investigated empirically and the requiredlevel of compensation, i.e. speed increase, can be determined.

A parameter of the operation of the pump that can be controlled by thepump controller may be an electrical parameter. The pump controller canvary the voltage that is supplied to the pump. Alternatively oradditionally, the pump controller can vary the current that is suppliedto the pump. In this way, the operation of the pump can be adjusted inorder to compensate for a loss of efficiency.

In a related manner, the pump controller may be configured to vary thepower that is supplied to the pump. Again, in this way any loss ofefficiency in the operation of the pump can be compensated by increasingthe power of pump operation.

It is possible for the pump controller to vary just one of the pump'soperational parameters or vary a plurality of the pumps operationalparameters, as required.

The present invention is particularly useful for beverage preparationmachines that prepare a beverage in a beverage preparation package. Asnoted above, the quality of the resulting beverage is dependent on thevolume of liquid that is provided. Therefore, a consistent volume willresult in a consistent desired quality of beverage.

The beverage preparation machine of the present invention may have apackage receiving means for receiving a beverage preparation packagethat contains beverage preparation ingredient, wherein the dispensingoutlet is configured to dispense the liquid into the beveragepreparation package when the beverage preparation package is present inthe package receiving means.

The package receiving means is capable of holding a beverage preparationpackage so that the dispensing outlet can inject the liquid into thepackage. This allows the preparation of the beverage within the package,since the package contains the beverage preparation ingredient. Thebeverage preparation ingredient may be coffee grounds, tea leaves, orchocolate powder etc. The prepared beverage will then leave the beveragepreparation package, as is conventional in the art.

The beverage preparation machine may comprise a beverage containerreceiving station for receiving a beverage container, wherein thebeverage preparation machine is configured so that when the beveragecontainer is present in the beverage container receiving station, it iscapable of receiving a beverage from the beverage preparation packagewhen the beverage preparation package is present in the packagereceiving means. In this way the beverage preparation machine can beused so as to prepare the beverage and then allow the beverage to beconveyed to a beverage container for the user to then consume thebeverage.

The present invention also provides a method for operating a beveragepreparation machine of the present invention, comprising the steps of:initiating a first operation of the pump; and initiating a secondoperation of the pump after a first time period; wherein the secondoperation of the pump is controlled on the basis of a characteristic ofthe first operation of the pump.

This method allows the second operation of the pump to be compensatedwhen required based on the first operation of the pump. In this manner,the consistency in the dispensed volume can be increased.

When the first time period is less than a critical value, the secondoperation of a pump may be different to the first operation of the pump.This accounts for the hysteresis in the performance of the pump based onrecent operational history.

In order to compensate for the recent operational history, as notedabove, the second operation of the pump may be for a longer time thanthe first operation of the pump, and/or at a higher speed than the firstoperation of the pump, and/or at a higher power than the first operationof the pump.

In this way, the operation of the pump is adjusted so as to increase theconsistency of the dispensed volume of liquid.

The aspects of the beverage preparation machine described above can beutilised with the method of the present invention.

The present invention will now described with reference to the followingdrawings.

FIG. 1 depicts the variation in dispensed liquid volume with number ofconsecutive vends in a machine without a compensation mechanism.

FIG. 2 depicts a schematic diagram of beverage preparation apparatus ofthe present invention.

FIG. 3 depicts a graph of the dispensed volume with continuous vends fora beverage preparation apparatus of the present invention.

A beverage preparation apparatus of the present invention is depicted ina schematic manner in FIG. 2. The beverage preparation apparatus 2comprises a user input means 4 in the form of a touch panel. The userinput means 4 is connected to the pump controller 6 such that electricalsignals can be communicated to the pump controller 6. The pumpcontroller 6 controls pump 8 by being connected to the pump 8 so thatelectrical signals can be conveyed. Pump 8, when operating, conveysliquid from reservoir 10 to heater 12 and through to outlet 14. In thismanner, the pump controller 6 can operate pump 8 so as to provide liquidfrom the reservoir 10 to be dispensed from outlet 14. The presence ofheater 12 allows the water to be heated as it passes on its way to theoutlet in order to produce hot beverages when desired. The tubingpresent between the pump 8 and the outlet 14 additionally has a valve 16that can prevent undesired flow of liquid out of the outlet.

The beverage preparation apparatus 2 has a package receiving means 18that retains a beverage preparation package 20. The outlet 14 is in theform of a needle that can pierce the top of the beverage preparationpackage 20 and so provide liquid directly into the beverage preparationpackage. The beverage preparation package has a heat sensitive seal onits lower edge 22 that can open under the action of the hot water thatis injected into the beverage preparation package 20. In this way, thebeverage can exit the beverage preparation package.

The beverage preparation machine has a beverage container receivingstation 24 that can receive beverage container 26. The cup receivingstation 24 ensures that the user places the beverage container 26 in thecorrect location to receive the prepared beverage from beveragepreparation package 20.

The pump controller 6 is programmed to vary the operational time of pump8 based on the operational history of pump 8.

An approach that is of general applicability and is not limited to theparticular setup of FIG. 2 (but can be utilised with this setup) willnow be described.

The pump controller 6 operates pump 8 for a time (Vend time) dictated bythe following equation:

Vend time (secs)=T _(fixed) +T1+T2+T3

Wherein T_(fixed) is a baseline operational time for the pump, T1 is anyadjustment to the vend time introduced during initial calibration of thebeverage preparation apparatus, T2 is the time dictated by the userinput from user input panel 4 (an optionally longer time for a largerrequired volume), and T3 is any volume variability compensation timethat is based on the operational history of the pump 8.

Therefore, in the present example, the pump compensation is carried outby adjusting the operational time of the pump, although, as acknowledgedabove, other operational parameters of the pump may be varied.

In order to compensate for the decreasing vend volume depicted in FIG.1, the following empirical compensation approach was formulated.

If the pump has not been operated for more than four minutes, then T3 inequation above is set at 0 and no compensation for recent operation isrequired. Whereas if a previous vend has occurred in the last fourminutes then an adjustment factor is required. Accordingly, T3 wasempirically found to be as follows:

T3=N×0.4 (N<10).

Wherein N is the number of vends that have occurred in the previous fourminutes up to a maximum value of 9. Accordingly, 0.4 seconds is addedfor each vend that has occurred in the previous four minutes.

The effect of applying this compensation mechanism can be appreciated bycomparing FIGS. 1 and 3. FIG. 3 depicts the volume dispensed withcontinuous vends with the compensation mechanism compared to the exactsame setup without the compensation mechanism reported in FIG. 1. It canbe seen that the compensation mechanism significantly increases theconsistency of the dispensation of liquid without the need for aflowmeter.

The foregoing description describes aspects of the invention but shouldnot be considered limiting. The invention is defined in the followingclaims.

1. A beverage preparation machine comprising: a housing; a reservoir forcontaining a liquid, wherein the reservoir is situated within thehousing; a dispensing outlet for dispensing the liquid; a pump situatedbetween the reservoir and the dispensing outlet; a user input meanssituated on an outer surface of the housing; and a pump controllerconfigured to operate the pump for conveying liquid from the reservoirto the dispensing outlet for dispensing the liquid, wherein the inputmeans is capable of communicating with the pump controller in order toinitiate an operation of the pump; and the pump controller is configuredto operate the pump based on a characteristic of a previous operation ofthe pump.
 2. The beverage preparation machine of claim 1, wherein thecharacteristic of the previous operation of the pump comprises a timethat has elapsed since the previous operation of the pump.
 3. Thebeverage preparation machine of claim 2, wherein the characteristic ofthe previous operation of the pump comprises a time that has elapsedbetween each of a plurality of previous operations of the pump.
 4. Thebeverage preparation machine of claim 1, wherein the characteristic ofthe previous operation of the pump comprises a frequency of a pluralityof previous operations of the pump.
 5. The beverage preparation machineof claim 1, wherein the pump controller is configured to vary the timeof operation of the pump based on the characteristic of the previousoperation of the pump.
 6. The beverage preparation machine of claim 1,wherein the pump controller is configured to vary the speed of operationof the pump based on the characteristic of the previous operation of thepump.
 7. The beverage preparation machine of claim 1, wherein the pumpcontroller is configured to vary an electrical parameter of the pumpbased on the characteristic of the previous operation of the pump. 8.The beverage preparation machine of claim 1, wherein the pump controlleris configured to vary the power of operation of the pump based on acharacteristic of the previous operation of the pump.
 9. The beveragepreparation machine of claim 1, wherein the pump is a reciprocatingpositive displacement pump.
 10. The beverage preparation machine ofclaim 9, wherein the pump comprises a shuttle mechanism.
 11. Thebeverage preparation machine of claim 1, further comprising a packagereceiving means for receiving a beverage preparation package thatcontains beverage preparation ingredient, wherein the dispensing outletis configured to dispense the liquid into the beverage preparationpackage when the beverage preparation package is present in the packagereceiving means.
 12. The beverage preparation machine of claim 11,further comprising a cup receiving station for receiving a beveragecontainer, wherein the beverage preparation machine is configured sothat the beverage container in the cup receiving station is capable ofreceiving a beverage from the beverage preparation package when thebeverage preparation package is present in the package receiving means.13. The beverage preparation machine of claim 1, wherein the beveragepreparation machine does not comprise a flowmeter for measuring thevolume of liquid conveyed from the reservoir to the dispensing outlet.14. A method for operating a beverage preparation machine of claim 1,comprising the steps of: initiating a first operation of the pump; andinitiating a second operation of the pump after a first time period;wherein the second operation of the pump is based on a characteristic ofthe first operation of the pump.
 15. The method of claim 14, whereinwhen the first time period is less than a critical value, the secondoperation of the pump is different to the first operation of the pump.16. The method of claim 15, wherein the second operation of the pump isfor a longer time than the first operation of the pump.
 17. The methodof claim 15, wherein the second operation of the pump is at a higherspeed than the first operation of the pump.
 18. The method of claim 15,wherein the second operation of the pump is at a higher power than thefirst operation of the pump.